Latch release system

ABSTRACT

This is a latch release system which uses a manually actuated switch means electrically connected to a release mechanism including a heat motor and gear means. The heat motor and gear means have means of electrically opening the circuit instituted by the manual switch. The gear means turns a shaft which is connected at one end to a keylock and which is passed through a latch mechanism and is adapted to turn in one direction without turning the keylock.

United States Patent [72] Inventors Peter T. Carlson Canton; Frederick J. Weremey, Milton; Edward B. Mitchell, Belmont, Mass. [21 Appl. No. 759,286 [22] Filed Sept. 12, 1968 [45] Patented Mar. 23, 1971 [73] Assignee United-Carr Incorporated- Boston, Mass.

[54] LATCH RELEASE SYSTEM 6 Claims, 9 Drawing Figs.

[52] US. Cl 1. 70/241, 70/257, 70/264, 292/201 [51] Int. Cl E05b 65/12 [50] Field of Search 70/240,

241, 256, 257, 262, 263, 264,265; 292/144, 201, (D), (RDLL); 180/111, 112, 113, 114

[56] References Cited UNITED STATES PATENTS 2,943,880 7/1960 Joachim et al 292/201 3,016,968 1/1962 Lonz et al. 180/82 3,378,291 4/1968 Brian 292/68 Primary Examiner--Marvin A. Champion Assistant Examiner-Robert L. Wolfe AttorneysPhilip E. Parker, Gordon Needleman, James R.

O'Connor, John Todd, Hall and l-loughton and J. Y.

, Houghton ABSTRACT: This is a latch release system which uses a manually actuated switch means electrically connected to a release mechanism including a heat motor and gear means. The heat motor and gear means have means of electrically opening the circuit instituted by the manual switch. The gear means turns a shaft which is connected at one end to a keylock and which is passed through a latch mechanism and is adapted to turn in one direction without turning the keylock.

PATENTED MAR 2 31971 sum 1 OF 4 mm. mm m VR m T. m H P FREDERIC .WEREMEY BY EDWARD a. MITCHELL %za 07 ATTORNEY I PAH-WEDM23191: 3572068 sum 2 0f 4 l I w n 9 E 8 w JI - 3 INVENTORS PETER T. CARLSO a q- FREDERICK J. WEREIVD m BY EDWARD B. MHCHELL ATTO RNEY PAIEN-TEMmnsn I 3572.068

sum 3 or 4 INVENTORS PETER T. CARLSON FREDERICK J. WEREMEY BY EDWARD B. MITCHELL ATTORNEY PATENTEU mes 1911 3,572,068 saw u 0F. 4 I

. INVENTORS PETER T. CARLSON FREDERICK J. WEREMEY BYEDWARD B. MITCHELL ATTOR NEY LATCH RELEASE SYSTEM BACKGROUND OF THE INVENTION In the past there have been several different methods of remotely actuating door lock means used on a motor vehicle. Many of these systems have been concerned with means of opening the covers on gasoline tanks although some of the later systems have been directly concerned with door latches and door latching systems for the vehicle. One of the earlier systems is disclosed in the patent to .l.W FitzGerald, U.S. Pat. No. 1,876,894, issued Sept. 13, 1932. This system discloses the use of a bimetallic strip which moves a latch member into and out of engagement with another latch member. An electrical circuit was used to actuate the' bimetallic stripby applying heat to the same on proper actuation'of a switch. The H. E. Kelly patent, U.S. Pat. No. 2,035,895, issued Mar. 31, 1936,

utilizes a solenoid core as the latch bolt. The solenoid in this case was actuated by a remote control switch. Both the Fitz- Gerald and Kelly disclosures do not utilize a compatible keylock system. The Lenz et al. patent, US. Pat. No.

3,016,968, issued Jan. 16, 1962, discloses a remote control lock system which interposes a remotely controlled power adapter between the lock and the latch mechanism. In this case a vacuum motor is used as the transducer. Finally the patent to Schmalfeldt, U.S. Pat. No. 3,062,033, issued Nov. 6, I962, uses a Bowden wire mechanism as the remote control means of opening a vehicle trunk door.

SUMMARY OF THE INVENTION The inventors latch release system has four major components: namely, an independent lock assembly; a latch assembly including a transmission shaft means; a remote controlled release mechanism including a circuit-interrupting means and a transducer; and, a switch means.

The lock assembly and the latch. assembly are both well known in the art and the Lenz et al. patent mentioned heretoforeindicates one of the well-known constructions of these two components. The inventors have included in the transmission shaft means a freewheeling connection which allows the key of the lock assembly to rotate the shaft inone direction and allows the energy imparted by the transducer to rotate the .shaft in the opposite direction only. The transmission shaft ex- 1 tends from the lock assembly to the freewheeling connection;

thence through the latch assembly to the release mechanism. This positional relationship between the latch assembly, the lock assembly and the remote control release mechanism is important and will be discussed more extensively hereinafter.

The rivet holding the driving gear and the piston arm of the release mechanism are both current carrying members and are part of the circuit which includes the core element of the magnetic holding switch. The piston arm rotates the driving gear by hearing against the pin of the drivinggear until the piston arm moves over and past the pin thereby opening the switch circuit and collapsing the magnetic field-The circuit will now remain open until manually actuaterl'as will be more fully described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view showing the main components of the assembly;

FIG. 2 is a section taken on line 2-2 of FIG. 1; FIG. 3 is a side elevation partly in section'and partly schematic showing the remote controlled release mechanism and the switch means;

FIG. 4 is a section taken on line H of FIG. 3;

FIG. 5 is a section taken on line 5-5 of FIG. 3;

FIG. 6 is a sectional view of the heat motor;

FIG. 7 is a section taken on line 7-7 of FIG. 6;

FIG. 8 is a side elevation of the armature assembly; and,

FIG. 9 is a perspective of the latch.

5 DESCRIPTION OF THE PREFERRED EMBODIMENT The holding switch assembly comprises a plunger 10 which is tubular in configuration and which is open at one end and closed at the other. A radial flange 12 extends outwardly adjacent its open end and a cylindrical nib 14 extends from the inner surface of the closed end of the plunger 10 for a purpose to be described hereinafter. The carrier l6 another component of the holding switch, has a cup-shaped portion and a cylindrical shaft portion 18 which extends axially from the bottom of the cup-shaped portion as shown in FIG. 3. The external diameter of the cup-shaped portion is less than the internal diameter of the cavity of the plunger 10. A helical compression carrier spring 20 is located within the cavity of the plunger 10 and circumscribes the nib I4. The carrier 16 is slideably engaged within the cavity of the plunger 10 with the remaining portion of the carrier spring 20 extending into the cup-shaped portion or well of the carrier I6 and abutting the bottom thereof as shown in FIG. 3. A carrier washer 21 having an aperture is engaged to the plunger 10 and the carrier 16 by passing the shaft portion 18 of the carrier 16 through the aperture until the carrier washer 21 butts against the shoulder formed by the bottom of the cup-shaped portion of the carrier 16 with the smaller diameter shaft portion 18 and against the internal shoulder formed in the plunger 10 as shown in FIG. 3. The ultimate holding force against the carrier washer 21 is supplied by a conical, coil plunger spring 22 which is butted against the lower surface of the carrier washer 21 and which circumscribesthe shaft portion 18.

The core subassembly of the holding switch comprises an insulating base 28 generally rectangular in configuration which has a core blade terminal 30 passed through an aperture formed therein. A soft ironcore 32 is in superposed abutting relationship to a portion of the core terminal 30 and the base 28. The core 32 comprises a rectangular solid base portion having two rectangular solid blocks one of which extends from a surface adjacent each end and another rectangular solid block which extends from the opposite surface adjacent one end as shown in FIG. 3. There are a pair of cylindrical protrusions 40 which are used in the assembly operation as will be explained hereinafter. The armature 34 includes a striplike portion having an aperture centrally formed therein through which the upper contact 42 is engaged. The magnetic strip 36 is mounted on top of the armature 34 and is held in engagement therewith by inserting the upper contact 42 through an aperture formed in the magnetic strip 36 and swedging it over. It is possible to reverse the position of the magnetic strip 36 and the armature 34 if desired. The lower end of the armature 34 and the magnetic strip 36 are free; that is, they are not physically attached together although they are in butting relationship as shown in FIG. Although we could coat the armature 34 with a magnetic material or use a bimetallic strip, the inventors have decided to utilize the bulk properties of a strip, the inventors have decided to utilize the bulk properties of a strip of magnetic material. Thus one of the purposes of the armature 34, which is formed of a spring steel, is to supply spring flexibility to the comparatively soft material which forms the magnetic strip 36. The armature 34 has an arm 48 which extends from a side edgeand which has a pair of spaced holes formed along its mid line. The two apertures formed in the arm 48 of the armature 34 are engaged with the protrusions 40 which extend from the core 32 as shown in FIG. 8. There is a possibility that adjustment may be required in the magnetic strip 36. This contingency is provided for by bowing the strip proximate its terminal end. Adjustments can be provided by tweaking the magnetic strip near the bowed portion. It is important that the magnetic strip maintain the same shape. The wire blade terminal 50 isengaged to the base 28 in a manner well known in the art through a slot formed in the base 28. Prior to assembling the core 32 with the base 28 and the armature 34, a coil of conductive wire is formed or wrapped around the core body proper and has two terminations one of which is 5 soldered to the wire blade terminal 50. A lower contact 44 and a contact spring 52 are assembled together forming a lower contact subassembly. The contact spring 52 comprises a flat flexible conductive material such as spring steel which is bent to form an upper arm, a support portion at right angles to the upper arm and a lower arm at right angles to the support portion and in substantially parallel relationship with the upper arm. The lower contact 44 is engaged through an aperture formed in the upper arm of the contact spring 52 and swedged into engagement therewith and the lower arm is attached to the base by an eyelet or other appropriate attaching means. The top portion of the lower contact 44 is on a plane above the upper plane of the rectangular boxlike portion of the core 32. This relationship is maintained so that the upper contact 42 will electrically engage the lower contact 44 prior to the time that the magnetic strip 36 engages the core 32. The other end of the core wire 54 is attached to the contact spring 52 to complete its circuit.

The housing subassembly includes an aluminum boxlike housing 56 having an aperture formed through its cap portion. A bushing 58 formed of aluminum is curled into the aperture formed in the housing. Then the assembly of the plunger 10, the carrier spring 20, the carrier 16 and the carrier washer 21 would be dropped into the bushing 58 until the flange l2 butts against the bushing 58. The plunger spring 22 would then be placed in circumscribing relationship to the shaft portion 18 with an end butted against the support washer 24 which in turn rests on the tabs 26 which extend from the sidewalls of the housing 56. An aperture is formed in the support washer 24 through which the shaft portion 18 of the carrier 16 can extend when the plunger is depressed. The housing 56 with its subassemblies is now engaged to the base 28 with its subassemblies completing the total assembly of the magnetic holding switch.

Generally speaking, the switch can be considered as one which is manually closed and electrically opened. As the plunger 10 is depressed the carrier spring 20 and the carrier 16 move down compressing the plunger spring 22. As pressure on the plunger 10 continues the shaft portion 18 passes down through the aperture in the support washer 24 until the terminal end of the shaft portion 18 bears against the magnetic strip 36. The shaft portion 18 will continue to push the magnetic strip 36, the armature 34 and the upper contact 42 toward the core 32 and the lower contact 44. When the upper contact 42 engages the lower contact 44 a circuit is completed through the wire core 54 and the core 32 exerts a magnetic force of attraction on the armature 34 and its associated magnetic strip 36. The manual force exerted by the shaft 18 of the carrier 16 continues concurrently with this magnetic force until the armature 34 physically butts against the core 32. With these two elements engaged and the circuit in operation the plunger 10 may now be released without disturbing the magnetic circuit or the switch circuit connected to the heat motor 62. To provide over-travel after the shaft 18 has engaged the fixed position of the core 32 through the armature 34 and the magnetic strip 36 the carrier spring 20 will allow the plunger 10 to continue a short distance after this mentioned engagement.

The release mechanism assembly comprises a heat motor 62, a driving gear 72 and an actuating gear 73. The basic ob ject of the release mechanism is to rotate a transmission shaft 60 which in turn will actuate a latch mechanism thus opening a door or the like. When the heat motor 62 is activated by the holding switch assembly the heat motor shaft 64 will start moving outwardly forcing the carrier piston 66 through the insulator 82 and one end of the support bracket 74. The carrier piston 66 circumscribes in a fixed relationship the heat motor shaft 64 and moves therewith. The carrier piston 66 has an integral piston arm 70 which extends outwardly at right angles therefrom and overlies the driving gear 72 which is rotatably attached to the support bracket 74 by a rivet 75. The rivet 75 makes electrical contact with the support bracket 74 and thence to ground. This means that the driving gear 72 is also connected to ground through the rivet 75. A return spring 76 say;

is wrapped around the carrier piston 66 engaged against the insulator 82 and has its opposite terminal end flexed against the piston arm holding it downwardly against the rivet 75. The return spring 76 also acts as a compression spring between the insulator 82 and an external shoulder of the carrier piston 66. Thus the return spring 76 functions both as a compression spring and as a torsion spring. The rivet is headed in such a way so that the piston arm 70 is spaced from the main body of the driving gear 72. A pin 78 extends at right angles from the driving gear 72 and is positioned directly in front of the forward surface of the piston arm 70. As the carrier piston 66 moves forward it compresses the return spring 76 and engages against the pin 78 rotating the driving gear 72 in a counterclockwise direction. This rotation of the driving gear 72 is translated to the meshed actuating gear 73 which rotates in a clockwise direction turning the transmission shaft 60 in that direction. This rotation of the driving gear 72 continues until the chamfer 84 which extends from the carrier piston 66 engages in a camming surface in the insulator 82 rotating the carrier piston 66 which in turn rotates the piston arm 70 away from the rivet 75 breaking that connection but still retaining the electrical connection through the pin 78. Since the electrical circuit is still complete the chamfer 84 continues its rotary or cam action with the insulator 82 which butts against the support 74 finally turning the piston arm 70 out of engagement with the pin 78 thus breaking the electrical circuit and stopping the action of the heat motor 62.

As the driving gear 72 rotated, it wound a driving gear torsion spring 91 which is now free to rotate the driving gear 72 back to a predetermined position. The predetermined position is fixed by a stop pin 92 which extends from the opposite side of the driving gear 72 from that of the pin 78 and its abutting relationship with a leaf spring 88 as will be more fully explained hereinafter.

As the piston arm 70 starts to rotate away from the rivet 75 a cam 86 integral with and extending from the carrier piston 66 simultaneously rotates away from a leaf spring 88 with its attached superposed abutted insulator 90. The assembly of the leaf spring 88 and the insulator 90 are fastened to the bracket 74 and are spaced therefrom for the major portion of their length allowing the leaf spring 88 to flex upwardly into the path ofa stop pin 92. When the piston arm 70 begins to return toward the rivet 75 its rotation is stopped because it butts against the top of the pin 78 allowing the leaf spring 88 to remain in its upper position. As the carrier piston 66 continues to move backward on a horizontal plane it frees itself from the top of the pin 78 and snaps in a rotary manner on to the rivet 75. As this snapping action occurs the cam 86 forces the leaf spring 88 downward to its original position disengaging it from the stop pin 92 which in turn allows the driving gear 72 to return to its original position along with the carrier piston 66.

The latch mechanism comprises a keyed cam 94 having a rectangular slot 96 formed therethrough. The cam 94 when turned clockwise by the transmission shaft 60 forces the locking bellcrank lever 100 to rotate clockwise moving its catch 102 away from the lock shoulder 104 of the latch plate 106. When the catch 102 fully disengages from the lock shoulder 104 the latch plate 106 is free to rotate in a counterclockwise direction. The force required to rotate the latch plate 106 is imparted by a torsion spring 108. When the latch plate 106 has completed its rotation the keeper is disengaged from the keeper receiving recess of the latch plate 106. The keeper 110 which extends from the lid of the automobile trunk and the latch assembly which is affixed to the automobile body proper are now separated and the lid springs open. In order to relatch the keeper 110 with the latch assembly the keyed cam 94 must rotate counterclockwise far enough so that the bellcrank lever 100 can rotate and place its catch 102 in the path of and into abutting relation with the lock shoulder 104. The torsion spring 108 is attached to both the bellcrank lever 100 and the latch plate 106 and supplies the energy for turning the bellcrank lever 100 into the path of the latch plate 106.

The transmission shaft 60 extends from the keylock 112 and into the actuating gear 73. It passes through the rectangular slot 96 of the'keyed cam 94 of the lock mechanism. The transmission shaft 60 comprises a rectangular forward portion having a-terminal end engaged withinthe keylock 112 and having a cup portion 116 at the other end. The cup portion 116 is in effect'a container opening away from-the terminal end and having a slot formed along its edge. The rear portion of the transmission shaft 60 comprises a rectangular extended por tion having an engagement end and having-a disc portion 120 which is perpendicular to the main axis of the rear shaft. A

, movable axially in relation to the rest of the subassembly as cylindrical pin 122 extends radially from the edge of the disc portion 120 in spaced relation to the rear shaft and is adapted to engage within the slot formed on the edge of the cup portion 116. The rear shaft is movably secured to the forward shaft by a disclike support ring 124. The support ring 124 is fastened as a cover to the edge of the cup-shaped portion 116 trapping the cylindrical pin 112 within the cup-shaped portion 116 while allowing the pin to move from one edge of the slot to the other.

When a key is turned clockwise in the keylock 112 the forward end of the transmission shaft 60 also turns clockwise. This action brings the edge of the slot against the pin 122 causing' it to move clockwise along with the rear portion of the transmission shaft 60. The rotation of the transmission shaft 60 will cause the keyed cam 94 .to rotate thereby unlocking the latched mechanism. a

When the rear end of the transmission shaft 60 is rotated in a counterclockwise direction by the actuating mechanism the keyed cam 94 will be rotated to release the latch mechanism. However this movement will move the pin 122 along the slot on the edge of the cup portion 116 without moving the forward portion of the transmission shaft 60 or the keylock 1 12.

The heat motor 62 comprises a tubular case or housing 126 having a large opening at one end and having a hemispherical configuration at the other end whichhas an aperture formed axiallytherethrough. An internal shoulder 128 is formed in close proximity to the open end. A flexible insulator 130 having a base portion with an arced external surface 132 and having a base portion with an arced external surface 132 and havinga tubular extension 134 extending therefrom, as shown in FIG. 1, is inserted into the case 126. The arced external surface 132 is butted against the internalarced surface of the hemispherical configuration. A terminal 136 is passed through one endof the helical heating coil 138 which is fixed within the case 126 and is passed through an aperture axially formed through the flexible insulator 130 to sandwich the end of the heating coil 138 between the head of the terminal 136 and the upper surface of the insulator 130. The shank portion of the terminal is press-fitted into the insulator 130, as shown in FIG.

6. This press fit tends to flare out the end of the tubular extension 134 and thereby prevents the insulator 130 from moving in relation to the case 126. The volume defined bythe case 126 is .then filled with the correct amount of wax to the internal shoulder 128 level. A support washer'140 having a central aperture is then placed in spaced 'relation'to the shoulder 128 proximate the open end of the case 126 and is then pressed into abutting relation with a coil of the heating coil 138 sandwiching it between the support washer 140 and the internal shoulder 128. A subassembly comprising a guide 142, an inner seal 144 and the heat motorshaft 64 closes theopen end of the case and is held in place by curling the edge of the open end over the guide 142 as shown in FIG. 6.-The shaft 64 is well as the case 126. A tubular inner shield 150 is used to insulate the heating coil 138 from the metal case 126. The arced configuration of the insulator 132 tends to distribute. the forces applied by the wax in a manner which assures a tight fit with the arced internal surface of the case 126 and thereby increases the efficiency of the seal.

We claim:

1. A latch release system comprising a lock assembly, a

latch assembly, a remote controlled release mechanism in cludmg a circuit-interrupting means and a transducer having a carrier piston, a switch means and a transmission shaft extending from the lock assembly through the latch assembly to the remote controlled release mechanism, the switch means electrically connected to the remote controlled release mechanism and the circuit-interrupting means comprising a drive means associated with the transmission shaft and having means associated therewith, the carrier piston having an extension in abutting relation to the means associated to the drive means and adapted to rotate away from the drive means on actuation of the transducer, the carrier piston and the means associated with the drive means being current carrying members and part of the circuit including the switch means.

2. A latch release system as set forth in claim 1 wherein the drive means comprises adrive gear meshed with an actuating gear and the means associated with the drive means is a rivet and the drive gear has a pin extending therefrom, the extension of the carrier piston having a forward edge in movable abutting relationship with the pin and in movable superposed abutting relationship with the pin and in movable superposed abutting relationship to the rivet.

3. A latch release system as set forth in claim 2 wherein an insulator member is spaced from the transducer and has an aperture formed therethrough and wherein a return spring circumscribes a portion of the carrier piston and is flexed against the piston arm and butts against the insulator member thereby functioning as a compression spring and a tension spring and wherein the terminal end of the carrier piston extends into the aperture formed in the insulator.

4. A latch release system as set forth in claim 3 wherein the circuit-interrupting means is fixed within a bracket and wherein the carrier piston has an integral cam portion extending downwardly therefrom adapted to movably engage a leaf spring and the leaf spring is adapted to engage a stop pin extending from the opposite side of the drive gear from the pin whereby the leaf spring will prevent movement of the drive gear in a predetermined direction when it is not fully engaged portion connected together by a freewheeling connection which comprises a cup portion associated with one of the shaft portions and a disc portion associated with the other shaft por-. 

1. A latch release system comprising a lock assembly, a latch assembly, a remote controlled release mechanism including a circuit-interrupting means and a transducer having a carrier piston, a switch means and a transmission shaft extending from the lock assembly through the latch assembly to the remote controlled release mechanism, the switch means electrically connected to the remote controlled release mechanism and the circuit-interrupting means comprising a drive means associated with the transmission shaft and having means associated therewith, the carrier piston having an extension in abutting relation to the means associated to the drive means and adapted to rotate away from the drive means on actuation of the transducer, the carrier piston and the means associated with the drive means being current carrying members and part of the circuit including the switch means.
 2. A latch release system as set forth in claim 1 wherein the drive means comprises a drive gear meshed with an actuating gear and the means associated with the drive means is a rivet and the drive gear has a pin extending therefrom, the extension of the carrier piston having a forward edge in movable abutting relationship with the pin and in movable superposed abutting relationship with the pin and in movable superposed abutting relationship to the rivet.
 3. A latch release system as set forth in claim 2 wherein an insulator member is spaced from the transducer and has an aperture formed therethrough and wherein a return spring circumscribes a portion of the carrier piston and is flexed against the piston arm and butts against the insulator member thereby functioning as a compression spring and a tension spring and wherein the terminal end of the carrier piston extends into tHe aperture formed in the insulator.
 4. A latch release system as set forth in claim 3 wherein the circuit-interrupting means is fixed within a bracket and wherein the carrier piston has an integral cam portion extending downwardly therefrom adapted to movably engage a leaf spring and the leaf spring is adapted to engage a stop pin extending from the opposite side of the drive gear from the pin whereby the leaf spring will prevent movement of the drive gear in a predetermined direction when it is not fully engaged by the cam.
 5. A latch release system as set forth in claim 4 wherein the edge of the aperture formed in the insulator member is adapted to engage a chamfer formed on the carrier piston whereby movement of the chamfer axially into the aperture and against the edge will rotate the carrier piston.
 6. A latch release system as set forth in claim 5 wherein the transmission shaft is divided into a forward portion and a rear portion connected together by a freewheeling connection which comprises a cup portion associated with one of the shaft portions and a disc portion associated with the other shaft portion the cup portion having a slot formed on an edge thereof and the disc portion having a pin extending radially from an edge thereof and movably positioned in the slot of the cup portion whereby movement of the cup portion in one direction only will move the disc portion. 